As a combustion apparatus of a gas turbine, there is a combustion apparatus which includes a pilot fuel nozzle, and a plurality of main fuel nozzles provided around the pilot fuel nozzle. In the combustion apparatus, the stability of main pre-mixed flames is improved in diffusion flames formed by the pilot fuel nozzle.
Patent Document 1 discloses a configuration in which a region which does not have fuel injection holes is provided in some of pilot fuel nozzles in a circumferential direction, and fuel injected from the pilot fuel nozzles is non-uniformly distributed in the circumferential direction. In addition, Patent Document 1 discloses a configuration which causes the fuel injection amount of the fuel between a plurality of main fuel nozzles to be different from each other so as to non-uniformly distribute the fuel, which is injected from the plurality of main fuel nozzles to the outer circumferential sides of the pilot fuel nozzles, in the circumferential direction.
According to this configuration, the lengths of flames formed by combustion of the fuel are different from each other in the circumferential direction, and since the heat release rate is distributed, combustion oscillation decreases.
Patent Document 2 discloses a configuration in which fuel injection holes are respectively provided at a plurality of positions different from each other in an axial direction in a plurality of main fuel nozzles. In addition, Patent Document 2 discloses a configuration in which the fuel injection holes are respectively provided at a plurality of positions different from each other in the axial direction in the plurality of main fuel nozzles, and fuel injection angles from the fuel injection holes are different from each other. According to this configuration, periods of time elapsed from when fuel (pre-mixed gas) injected from the main fuel nozzles reaches flames are different from each other between the plurality of fuel injection holes having different positions in the axial direction, and combustion oscillation decreases.